1. Field of the Invention
This invention relates to swimming apparatus and, in particular, to improved swim fins to be worn on the feet of a swimmer to increase his mobility and safety in the water.
2. Description of the Prior Art
In recent years there has been an increasing tendency of people to engage in water activities. Among the more popular of such water activities are swimming, snorkeling, scuba diving and the like. It has been found that improvements in apparatus for use during such water activities have enhanced the enjoyment and safety of people engaged in such activities.
Types of apparatus which are receiving ever increasing popularity are the flippers or swim fins. Swim fins are normally rubber or plastic devices secured to the feet of the swimmer in an effort to simulate the action of the horizontal tail fin of an aquatic mammal such as a dolphin or a whale, the webbed feet of a duck or the vertical tail fin of most fish. When a human swimmer participates in water activites with the aid of fins on his feet, his swimming speed is improved, his ability to tread water enhanced and his overall enjoyment of the activity greatly increased. Perhaps even more importantly, his safety is made greater when merely swimming or when participating in other aquatic events such as snorkeling or diving with self-contained underwater breathing apparatus, scuba gear.
A great many types of swim fins and related devices are on the market today. Prior patent disclosures illustrate the development of this technology to the present highly developed state that it enjoys today.
One early effort to provide for increased water safety and enjoyment is described in U.S. Pat. No. 1,841,904 to McGowan. According to that disclosure, an oval shaped device is strapped to each foot of a swimmer. Secured within the device, parallel with the sole of the foot, are a plurality of shutter plates in spaced orientation, one from another, in overlapping relationship. When a foot and associated device are moved downwardly the shutters close and the device offers resistance to further downward movement of the device, foot and swimmer. When the foot and device are moved upwardly, the shutters open in unison to easily permit the device and foot to be raised. As a result, treading water is made easier and less fatiguing, and the device thus promotes safety in the water along with enjoyment. To a lesser extent, it would appear that the McGowan device could also function for the purposes of the more modern swim fin.
The state of the art in swim fins has continued to develop through the years. Consider, for example, the fins disclosed in U.S. Pat. No. 3,055,025 to Ferraro and in U.S. Pat. No. 3,422,470 to Mares. Those disclosed devices resemble the modern fins of today in that they are of a one piece construction with an inboard end for receiving the foot of a wearer and a thin flexible outboard end or flipper to simulate the action of a webbed foot of a duck or a tail fin of an aquatic mammal. The disclosures of these patents discuss the benefits which accrue by the incorporation of an aperture or apertures in the thin flipper portion of the fin. But in one of these disclosures, that to Ferraro, an additional flap of material is used to close the apertures during one part of the kick cycle of the swimmer and to open the apertures on the other part of the kick cycle. According to the Mares disclosure, supplemental flaps are utilized in association with the apertures but are adapted to open the apertures during both portions of the kick cycle.
Subsequently, the development of swim fins included chambers along the axial lengths of the fins. Note, for example, U.S. Pat. No. 3,649,979 to MacNiel and U.S. Pat. No. 3,913,158 to Vilarrubus. According to these disclosures, the flat extended flipper portion of the fin includes two spaced parallel surfaces defining a chamber therebetween to pass water from an upper central portion of the flipper, the water inlet zone, to and through a water outlet zone at the outboard tip of the flipper directly into the water. In effect, the flipper material on opposite sides of the chamber acts as two flippers. According to the MacNiel disclosure, the cross section of the chamber decreases toward the tip of the flipper for improved efficiency. Conversely, Vilarrubus discloses increased efficiency by increasing the cross section of the chamber toward the tip of the flipper. Further, compartmentalizing of a chamber into laterally spaced parallel compartments is disclosed.
U.S. Pat. No. 4,083,071 to Forjot alleges an improvement over the structures of MacNiel and Vilarrubus by utilizing a single chamber along the length of the flipper of the fin but with water inlets both on the upper and lower faces of the fin. A flexible baffle to alternately open and close the upper and lower inlets determines whether water enters the chamber on either the upstroke or downstroke of the kick cycle of the swimmer.
Lastly, a relatively complex type of swim device is disclosed in U.S. Pat. No. 4,342,558 to Wilson. According to that disclosure, a pair of complex, cumbersome devices may be attached to the feet of a swimmer. The devices each include a rotatable hydrofoil operating with mechanisms to allegedly enhance a swimmers capabilities in the water while increasing his safety. This device could hardly be considered as a swim fin.
As illustrated by the great number of prior art patents, efforts are continuously being made in an attempt to solve the problem of designing a convenient, safe swim fin having particular utility in increasing the mobility, enjoyment, and safety of swimmers. None of these patents, however, discloses or suggests the present inventive combination of parts of the present inventive improved swim fin. The present invention achieves its purposes, objectives and advantages over the prior art structures through new, useful and unobvious elements with but a single part at a relatively low cost and through the utilization of only readily available materials and conventional components.
These objects and advantages should be construed as merely illustrative of some of the more prominent features and applications of the present invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or by modifying the invention within the scope of the disclosure. Accordingly, other objects and advantages as well as a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description describing the preferred embodiment of the invention in addition to the scope of the invention as defined by the claims taken in conjunction with the accompanying drawings.